KR102189378B1 - Molding resin composition including chlorinated vinyl chloride-based resin, and molded article thereof - Google Patents

Abstract

An object of the present invention is to provide a chlorinated vinyl chloride resin composition having excellent thermal stability and a molded article thereof. The present invention is a molding resin composition containing a chlorinated vinyl chloride resin, a heat stabilizer, and a polyhydric alcohol and/or partial ester of a polyhydric alcohol, wherein the chlorine content in the chlorinated vinyl chloride resin is 65% by weight or more and less than 72% by weight. The chlorinated vinyl chloride-based resin is based on the total number of moles of the structural unit (a) -CCl ₂ -, the structural unit (b) -CHCl- and the structural unit (c) -CH ₂ -, of the structural unit (a) The ratio is 17.5 mol% or less, the ratio of the structural unit (b) is 46.0 mol% or more, the ratio of the structural unit (c) is 37.0 mol% or less, and the thermal stabilizer is of the general formula Ca _1-x Mg _x ( The compound represented by OH) ₂ (in the formula, x satisfies the relationship represented by inequality 0 <x <1) and the compound represented by the general formula Ca _1-y Mg _y O (in the formula, y is inequality 0 < It provides a resin composition for molding containing at least one of (the relationship represented by y<1 is satisfied).

Description

Molding resin composition containing chlorinated vinyl chloride resin and its molded article {MOLDING RESIN COMPOSITION INCLUDING CHLORINATED VINYL CHLORIDE-BASED RESIN, AND MOLDED ARTICLE THEREOF}

The present invention relates to a resin composition for molding containing a chlorinated vinyl chloride resin and a molded article thereof.

The vinyl chloride resin composition is widely used, for example, as a material for a resin molded article such as a building material. Since the vinyl chloride resin composition may be processed at high temperature, it is required to have high thermal stability. In addition, it is necessary to have high thermal stability in order to obtain the thermal stability of the molded article. In addition, since the color tone is important to the resin molded article used as a building material, it is also necessary for the vinyl chloride resin composition to have color resistance. In order to improve various performances such as thermal stability and color resistance, vinyl chloride-based resins are generally added with a thermal stabilizer before melt molding.

Conventionally, as a heat stabilizer, a heat stabilizer containing heavy metals such as lead, cadmium, and tin has been used. However, as toxicity of heavy metals and adverse effects on the environment become a problem, thermal stabilizers or resin molded articles that do not contain highly toxic metals such as lead have been proposed. For example, in Patent Document 1, an acid clay and/or activated clay in a halogen-containing resin and a calcium hydroxide-based compound represented by the formula Ca _1-xy M ²⁺ _x Al _y (OH) ₂ (wherein M ^{2 +} is Mg , Zn, Cu, and the like, and x and y are in the range of 0≦x<0.4 and 0≦y<0.1, respectively). A stabilized halogen-containing resin composition comprising a composite of It is disclosed.

However, even if a mixture of acid clay and/or activated clay and a calcium hydroxide-based compound is used for the chlorinated vinyl chloride resin, there is a problem that stability is insufficient.

Japanese Patent Laid-Open Publication No. 2008-214466

An object of the present invention is to provide a resin composition for molding containing a chlorinated vinyl chloride resin having excellent thermal stability and a molded article thereof.

A resin composition for molding comprising a chlorinated vinyl chloride resin, a heat stabilizer, and a polyhydric alcohol and/or partial ester of a polyhydric alcohol, wherein the chlorine content in the chlorinated vinyl chloride resin is 65% by weight or more and less than 72% by weight, and the chlorinated In the vinyl chloride resin, the ratio of the structural unit (a) is 17.5 mol with respect to the total number of moles of the structural unit (a) -CCl ₂ -and the structural unit (b) -CHCl- and the structural unit (c) -CH _2- % Or less, the ratio of the structural unit (b) is 46.0 mol% or more, the ratio of the structural unit (c) is 37.0 mol% or less, and the thermal stabilizer is a general formula Ca _1-x Mg _x (OH) ₂ Compound represented by (in the formula, x satisfies the relationship represented by inequality 0 <x <1) and a compound represented by the general formula Ca _1-y Mg _y O (in the formula, y is inequality 0 <y <1 The resin composition for molding and a molded article molded from the resin composition containing at least one of) are provided.

Advantageous Effects of Invention According to the present invention, a resin composition for molding containing a chlorinated vinyl chloride-based resin having excellent thermal stability and a molded article thereof can be provided.

In addition, according to the present invention, it is possible to provide a molding resin composition having preferable tensile strength, tensile modulus, and heat distortion temperature and excellent mechanical properties, and a molded article thereof.

The resin composition for molding contains a chlorinated vinyl chloride resin (hereinafter referred to as "CPVC"), a heat stabilizer, and a partial ester of a polyhydric alcohol and/or a polyhydric alcohol.

The chlorine content in the CPVC is 65% by weight or more and less than 72% by weight. When the chlorine content is 65% by weight or more, it is possible to impart practically effective heat resistance to CPVC. When the chlorine content is less than 72% by weight, the productivity of the chlorination reaction that is practically reasonable can be ensured, and the moldability of the molding resin composition containing CPVC can be made sufficient.

CPVC is a resin obtained by chlorinating a vinyl chloride-based resin (PVC), and is a highly chlorinated resin having a chlorine content of approximately 65% by weight or more and less than 72% by weight. The chlorine content in CPVC can be measured by the method described in JIS K 7229.

The CPVC has a structural unit (a) -CCl ₂ -, a structural unit (b) -CHCl- and a structural unit (c) -CH ₂ -.

The proportion of the structural unit (a) is 17.5 mol% or less with respect to the total number of moles of the structural units (a), (b) and (c). The proportion of the structural unit (a) is preferably 2.0 mol% or more and 16.0 mol% or less.

The proportion of the structural unit (b) is 46.0 mol% or more with respect to the total number of moles of the structural units (a), (b) and (c). The proportion of the structural unit (b) is preferably 53.5 mol% or more, and more preferably 58.0 mol% or more and 70.0 mol% or less.

The proportion of the structural unit (c) is 37.0 mol% or less with respect to the total number of moles of the structural units (a), (b) and (c). The proportion of the structural unit (c) is preferably 35.8 mol% or less, and more preferably 1.0 mol% or more and 30.5 mol% or less.

Such CPVC has high thermal stability and good molding processability.

The molar ratio of the structural units (a), (b) and (c) contained in the molecular structure of CPVC reflects the site where chlorine is introduced when PVC is chlorinated. PVC before chlorination is ideally in a state where the structural unit (a) is 0 mol%, the structural unit (b) is 50.0 mol%, and the structural unit (c) is 50.0 mol%, but with chlorination, the structural unit (c) decreases, and constituent unit (b) and constituent unit (a) increase. At this time, if the constituent unit (a) of which steric hindrance is largely unstable increases too much, or if the part which is not chlorinated in the same particle of CPVC is skewed, the non-uniformity of the chlorinated state increases. When this non-uniformity becomes large, the thermal stability of CPVC is greatly impaired. However, CPVC in which the proportion of the structural unit (a) is 17.5 mol% or less, the proportion of the structural unit (b) is 46.0 mol% or more, and the proportion of the structural unit (c) is 37.0 mol% or less has high uniformity and good It has thermal stability.

The molar ratio of the structural units (a), (b) and (c) contained in the molecular structure of CPVC can be measured by molecular structure analysis using NMR. NMR analysis can be performed according to the method described in R. A. Komoroski, R. G. Parker, J. P. Shocker, Macromolecules, 1985, 18, 1257-1265.

As PVC, a vinyl chloride homopolymer, a copolymer of a monomer having an unsaturated bond copolymerizable with a vinyl chloride monomer and a vinyl chloride monomer, a graft copolymer obtained by graft copolymerization of a vinyl chloride monomer with a polymer, and the like can be used. These polymers may be used alone or in combination of two or more.

Examples of the monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer include α-olefins such as ethylene, propylene, and butylene; vinyl esters such as vinyl acetate and vinyl propionate; butyl vinyl ether, cetyl vinyl ether, etc. Vinyl ethers; (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl acrylate, and phenyl methacrylate; aromatic vinyls such as styrene and α-methylstyrene; vinylidene chloride And vinyl vinyl halides such as vinylidene fluoride; and N-substituted maleimides such as N-phenylmaleimide and N-cyclohexylmaleimide, and one or two or more of these are used.

The polymer for graft copolymerization of vinyl chloride is not particularly limited as long as it is graft polymerization of vinyl chloride, and examples include ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-carbon monoxide copolymer, ethylene-ethyl acrylate copolymer, Ethylene-butyl acrylate-carbon monoxide copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, acrylonitrile-butadiene copolymer, polyurethane, chlorinated polyethylene, chlorinated polypropylene, and the like. May be used, or two or more types may be used in combination.

The average degree of polymerization of PVC is not particularly limited, and is preferably 400 to 3,000 commonly used, and more preferably 600 to 1,500. The average degree of polymerization can be measured from the method described in JIS K 6720-2:1999.

The polymerization method of PVC is not particularly limited, and conventionally known water suspension polymerization, bulk polymerization, solution polymerization, emulsion polymerization, and the like can be used.

The non-chlorinated PVC moiety in the molecular structure of CPVC can be represented by -CH ₂ -CHCl-, and this is referred to herein as a VC unit. The CPVC used in the present invention preferably has a content of 4 or more VC units contained in the molecular structure of 30.0 mol% or less. Here, the VC unit of 4 or more characters means a part in which 4 or more VC units are continuously bonded.

The VC unit present in CPVC serves as a starting point for de-HCl, and if these VC units are continuous, a continuous de-HCl reaction called a zipper reaction is likely to occur. That is, as the content of the VC units of four or more VCs increases, de-HCl tends to occur, and the thermal stability in CPVC decreases. Therefore, it is preferable that it is 30.0 mol% or less, and, as for the content of the VC unit of four or more, it is more preferable that it is 28.0 mol% or less, it is still more preferable that it is 18.0 mol% or less, and it is especially preferable that it is 16.0 mol% or less.

The content rate of four or more VC units contained in the molecular structure can be measured by molecular structure analysis using the above NMR.

In CPVC used in the present invention, when the chlorine content is 65% by weight or more and less than 69% by weight, it is preferable that the UV absorbance at a wavelength of 216 nm is 0.8 or less. Moreover, when the chlorine content of CPVC is 69 weight% or more and less than 72 weight%, it is preferable that UV absorbance at a wavelength of 216 nm is 8.0 or less. In the ultraviolet absorption spectrum, a wavelength of 216 nm is a wavelength at which -CH=CH-C(=O)- and -CH=CH-CH=CH-, which are heterogeneous structures in CPVC, exhibit absorption.

From the value of the UV absorbance of CPVC, the heterogeneous structure in the molecular chain during the chlorination reaction can be quantified, and it can be used as an index of thermal stability. In the molecular structure of CPVC, the chlorine atom attached to the carbon next to the double bonded carbon is unstable. Therefore, dehydrochlorinated HCl occurs using the chlorine atom as a starting point. That is, the greater the value of UV absorbance at a wavelength of 216 nm, the more likely it is to de-HCl, and the lower the thermal stability. When the chlorine content is 65% by weight or more and less than 69% by weight, when the value of UV absorbance exceeds 0.8, the influence of heterogeneous structures in the molecular chain increases, and as a result, thermal stability decreases. When the chlorine content is 69% by weight or more and less than 72% by weight, when the value of UV absorbance exceeds 8.0, the influence of heterogeneous structures in the molecular chain increases, and thermal stability decreases.

In the CPVC used in the present invention, when the chlorine content is 65% by weight or more and less than 69% by weight, the time required for the amount of HCl dehydrogenated at 190°C to reach 7000 ppm from CPVC is preferably 60 seconds or more, and the chlorine content is In the case of 69% by weight or more and less than 72% by weight, the time is preferably 100 seconds or more.

CPVC causes pyrolysis at high temperatures, and generates HCl gas at that time. In general, as the chlorination degree of CPVC increases, the above-described VC unit decreases, so the amount of de HCl tends to decrease. However, as the degree of chlorination increases, a non-uniform chlorination state or heterogeneous structure increases, and thermal stability decreases. Therefore, by measuring the amount of de HCl, it is possible to analyze a heterogeneous state of chlorination or an increase in heterogeneous structure. For example, the time required to reach 7000 ppm of the amount of HCl dehydrogenated at 190°C can be used as an index of thermal stability, and the shorter the time, the lower the thermal stability.

When the chlorine content is 65% by weight or more and less than 69% by weight, if the time is less than 60 seconds, thermal stability is greatly impaired. Therefore, the time is preferably 60 seconds or longer, more preferably 70 seconds or longer, and particularly preferably 80 seconds or longer. In addition, when the chlorine content is 69% by weight or more and less than 72% by weight, if the time is less than 100 seconds, the thermal stability is greatly reduced, so that it is preferably 100 seconds or more, more preferably 120 seconds or more, and 140 seconds or more. It is particularly preferred.

The time at which the amount of de-HCl at 190°C reaches 7000 ppm can be measured as follows. First, 1 g of a chlorinated vinyl chloride resin was put into a test tube, heated at 190°C using an oil bath, and the generated HCl gas was recovered. The recovered HCl gas was dissolved in 100 ml of ion-exchanged water, and the pH was measured. Based on the value of pH, the concentration of HCl (ppm) (that is, how many g of HCl was generated per million g of chlorinated vinyl chloride resin) is calculated. The time for the HCl concentration to reach 7000 ppm is measured.

The resin composition for molding of the present invention contains a polyhydric alcohol and/or a partial ester of a polyhydric alcohol.

As the polyhydric alcohol, for example, mannitol, xylitol, sorbitol, trimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol, glycerin, and the like can be used.

The partial ester of a polyhydric alcohol refers to an ester in which at least one or more of the hydroxyl groups in the polyhydric alcohol is not esterified and remains a hydroxyl group. By using partial ester of polyhydric alcohol, dispersibility in CPVC can be improved. The partial ester of a polyhydric alcohol is obtained by making at least 1 type of said polyhydric alcohol and at least 1 type of mono or polycarboxylic acid react.

What is a partial ester of a polyhydric alcohol can be confirmed by measuring the hydroxyl value of this molecule according to JIS K 0070 (1992), for example.

Examples of mono or polycarboxylic acids forming partial esters of polyhydric alcohols include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, neodecanoic acid, 2-ethylhexyl acid, pella Argonic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, isostearic acid, stearic acid, 1,2-hydroxystearic acid, behenic acid, montanic acid, benzoic acid, Monochlorbenzoic acid, pt-butylbenzoic acid, dimethylhydroxybenzoic acid, 3,5-ditert-butyl-4-hydroxybenzoic acid, toluic acid, dimethylbenzoic acid, ethylbenzoic acid, cumic acid, n-propylbenzoic acid, aminobenzoic acid, N ,N-dimethylbenzoic acid, acetoxybenzoic acid, salicylic acid, pt-octylsalicylic acid, oleic acid, elaidic acid, linoleic acid, linolenic acid, thioglycolic acid, mercaptopropionic acid, and monocarboxylic acids such as octylmercaptopropionic acid, oxalic acid, malonic acid , Succinic acid, glutanic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, oxyphthalic acid, chlorphthalic acid, aminophthalic acid, maleic acid, fumaric acid, citraconic acid, metacon Dicarboxylic acids, such as acid, itaconic acid, aconitic acid, and thiodipropionic acid, etc. can be used.

Among the partial esters of polyhydric alcohols obtained from the above polyhydric alcohols and mono or polycarboxylic acids, pentaerythritol adipate, dipentaerythritol adipate, and dipentaerythritol are preferably used.

In the resin composition for molding of the present invention, the total content of the polyhydric alcohol and the partial ester of the polyhydric alcohol is a preferable lower limit of 0.05 parts by weight and a more preferable lower limit of 0.1 parts by weight when the content of the chlorinated vinyl chloride-based resin is 100 parts by weight. Parts, a preferable upper limit is 3 parts by weight, and a more preferable upper limit is 2 parts by weight. Stability can be improved by containing polyhydric alcohol and/or partial ester of polyhydric alcohol in this range.

The total content of the polyhydric alcohol and the partial ester of the polyhydric alcohol, when the content of the heat stabilizer is 100 parts by weight, a preferable lower limit is 1 part by weight, a more preferable lower limit is 2 parts by weight, a more preferable lower limit is 3.5 parts by weight, and a preferable upper limit is 150 parts by weight, a more preferable upper limit is 120 parts by weight, and a more preferable upper limit is 20 parts by weight.

The resin composition for molding of the present invention contains a heat stabilizer.

As a heat stabilizer, a compound represented by the general formula Ca _1-x Mg _x (OH) ₂ (in the formula, x satisfies the relationship represented by the inequality 0 <x <1) and the general formula Ca _1-y Mg _y O At least one of the compounds represented by (in the formula, y satisfies the relationship represented by inequality 0<y<1) is used. The x is preferably 0.1 or more and 0.5 or less. The y is preferably 0.1 or more and 0.5 or less.

In the resin composition for molding of the present invention, when the content of the chlorinated vinyl chloride-based resin is 100 parts by weight, the content of the heat stabilizer is 0.4 parts by weight, a more preferable lower limit is 0.7 parts by weight, and a preferable upper limit is 10 parts by weight. Parts, a more preferable upper limit is 6 parts by weight. By containing the heat stabilizer in this range, the heat stability can be further improved, and the good appearance of the molded article can be maintained.

The thermal stabilizer is typically in the shape of particles having an average secondary particle diameter of 0.1 to 3 µm.

It is preferable that the resin composition for molding of the present invention further contains a stabilizing aid. By containing a stabilizing aid, thermal stability can be further improved.

The added amount of these stabilization aids is, based on 100 parts by weight of CPVC, a preferable lower limit is 0 parts by weight, a more preferable lower limit is 0.01 parts by weight, a more preferable lower limit is 0.05 parts by weight, a preferable upper limit is 8 parts by weight, and a more preferable upper limit is 5 Parts by weight, a more preferable upper limit is 3 parts by weight.

For example, organic acid salts, epoxidized soybean oil, epoxidized amani soybean oil, epoxidized tetrahydrophthalate, epoxy compounds such as epoxidized polybutadiene, organic phosphorus compounds, phosphorous acid esters, phosphoric acid esters, antioxidants, metals such as calcium hydroxide and sodium hydroxide Hydroxide, sodium adipate, hydrotalcite, and zeolite. These may be used alone or in combination of two or more.

Examples of the organic acid salts include sodium salts, calcium salts, magnesium salts, and potassium salts of organic acids. Examples of organic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, neodecanoic acid, 2-ethylhexyl acid, pelargonic acid, capric acid, undecanoic acid, lauric acid, tri Decanoic acid, myristic acid, palmitic acid, isostearic acid, stearic acid, 1,2-hydroxystearic acid, behenic acid, montanic acid, benzoic acid, monochlorbenzoic acid, pt-butylbenzoic acid, dimethylhydroxybenzoic acid, 3 ,5-ditert-butyl-4-hydroxybenzoic acid, toluic acid, dimethylbenzoic acid, ethylbenzoic acid, cumic acid, n-propylbenzoic acid, aminobenzoic acid, N,N-dimethylbenzoic acid, acetoxybenzoic acid, salicylic acid, pt-octyl Monovalent carboxylic acids such as salicylic acid, oleic acid, elaidic acid, linoleic acid, linolenic acid, thioglycolic acid, mercaptopropionic acid, octylmercaptopropionic acid, oxalic acid, malonic acid, succinic acid, glutanoic acid, adipic acid, pimelic acid, water Berlic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, oxyphthalic acid, chlorphthalic acid, aminophthalic acid, maleic acid, fumaric acid, citraconic acid, metaconic acid, itaconic acid, aconitic acid, thiodipropionic acid, etc. Di or triester compounds of trivalent or tetravalent carboxylic acids such as divalent carboxylic acid and monoester or monoamide compounds thereof, hemimelitic acid, trimellitic acid, melophanoic acid, pyromellitic acid, and melitic acid Contains. At this time, all of the hydroxyl groups of the alcohol component used as the raw material of the ester are esterified.

Moreover, as a stabilizing aid, it is preferable that the said organic acid salt is a higher fatty acid salt in order to improve the initial coloring property.

Although it does not specifically limit as said higher fatty acid, For example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, neodecanoic acid, 2-ethylhexyl acid, pelargonic acid, capric acid , Undecanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, isostearic acid, stearic acid, 1,2-hydroxystearic acid, behenic acid, montanic acid, benzoic acid, monochlorbenzoic acid, pt- Butylbenzoic acid, dimethylhydroxybenzoic acid, 3,5-ditert-butyl-4-hydroxybenzoic acid, toluic acid, dimethylbenzoic acid, ethylbenzoic acid, cumic acid, n-propylbenzoic acid, aminobenzoic acid, N,N-dimethylbenzoic acid, Monocarboxylic acids such as acetoxybenzoic acid, salicylic acid, pt-octylsalicylic acid, oleic acid, elaidic acid, linoleic acid, linolenic acid, thioglycolic acid, mercaptopropionic acid, octylmercaptopropionic acid, oxalic acid, malonic acid, succinic acid, glutanoic acid, Adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, oxyphthalic acid, chlorphthalic acid, aminophthalic acid, maleic acid, fumaric acid, citraconic acid, metaconic acid, itaconic acid, acco Nitric acid and thiodipropionic acid are mentioned. In particular, stearic acid, 1,2-hydroxystearic acid, lauric acid, palmitic acid, myristic acid, behenic acid, and montanic acid are preferable.

Examples of the metal components of the higher fatty acid salts include zinc, magnesium, calcium, lithium, and barium. Among them, zinc and magnesium are preferable.

The amount of the higher fatty acid salt added is preferably 0.01 parts by weight, a more preferable lower limit is 0.05 parts by weight, a preferable upper limit is 5.0 parts by weight, and a more preferable upper limit is 3.0 parts by weight, based on 100 parts by weight of CPVC.

It is preferable that the resin composition for molding of the present invention does not contain ?-diketone. β-diketone is a component incorporated in conventional heat stabilizers to improve heat stability. However, when a heat stabilizer containing β-diketone is used, the appearance of the molded article is liable to be damaged when the resin composition is molded by extrusion or injection molding to produce a molded article. For example, yellow to reddish-brown stripes with a thickness of about 0.1 to 1 mm parallel to the flow direction of the resin are generated on the surface of the molded article. The molded article whose appearance is damaged in this way becomes a defective product. In particular, when a die used for a long time is used, such defective products are liable to occur. However, according to the present invention, it is possible to provide a molding resin composition having excellent thermal stability without using a thermal stabilizer containing β-diketone.

According to the configuration of the present invention as described above, it is possible to provide a molding resin composition having excellent thermal stability.

Next, the above resin composition for molding and a method for producing a molded article will be described.

The manufacturing method of the resin composition for molding is to prepare a suspension by suspending a vinyl chloride-based resin in an aqueous medium in a reaction vessel, introducing chlorine into the reaction vessel, and heating the suspension to chlorine the vinyl chloride-based resin. Then, the step of preparing a chlorinated vinyl chloride resin, and a compound represented by the general formula Ca _1-x Mg _x (OH) ₂ as a heat stabilizer in the chlorinated vinyl chloride resin (wherein x is inequality 0 < at least one of x<1 satisfies the relationship represented by 1) and the compound represented by the general formula Ca _1-y Mg _y O (wherein y satisfies the relationship represented by inequality 0<y<1), It includes a step of adding and mixing a polyhydric alcohol and/or a partial ester of a polyhydric alcohol.

As the reaction vessel used for the chlorination reaction, for example, a generally used vessel such as a glass-lined stainless steel reaction vessel or a titanium reaction vessel may be used.

The method of preparing a suspension by suspending a vinyl chloride-based resin in an aqueous medium is not particularly limited, and a cake-like PVC obtained by demonomerizing PVC after polymerization may be used, or the dried product may be suspended again in an aqueous medium. Alternatively, a suspension from which a substance undesirable for the chlorination reaction has been removed from the polymerization system may be used, but it is preferable to use a cake-like resin obtained by demonomerizing PVC after polymerization.

As the aqueous medium, for example, ion exchange-treated pure water can be used. The amount of the aqueous medium is not particularly limited, but is generally preferably 2 to 10 parts by weight based on 100 parts by weight of PVC.

The chlorine introduced into the reaction vessel may be either liquid chlorine or gaseous chlorine. In order to inject a large amount of chlorine in a short time, it is efficient to use liquid chlorine. Chlorine may be added during the reaction in order to adjust the pressure or to replenish chlorine. At this time, in addition to liquid chlorine, gaseous chlorine may be appropriately blown. It is preferable to use chlorine after purging 5 to 10% by weight of the bomb chlorine.

The gauge pressure in the reaction vessel is not particularly limited, but the higher the chlorine pressure is, the more easily the chlorine penetrates into the inside of the PVC particles, so the range of 0.3 to 2 MPa is preferable.

After introducing chlorine, the suspension is heated to chlorine the vinyl chloride resin. Thereby, a chlorinated vinyl chloride resin is obtained. By heating, the bonding of PVC and chlorination due to excitation of chlorine are promoted. This chlorination is performed without ultraviolet irradiation. In the case of chlorination reaction by UV irradiation, the amount of light energy required for chlorination of PVC is greatly affected by the distance between the PVC and the light source. Therefore, the amount of energy to be received is different between the surface and the inside of the PVC particles, and chlorination does not occur uniformly. As a result, CPVC with low uniformity is obtained. On the other hand, in the method of chlorinating by heat without UV irradiation, a more uniform chlorination reaction becomes possible, and CPVC with high uniformity can be obtained.

It is preferable that the heating temperature is in the range of 70 to 140°C. If the temperature is too low, the chlorination rate decreases. If the temperature is too high, a de-HCl reaction occurs in parallel with the chlorination reaction, and the obtained CPVC is colored. The heating temperature is more preferably in the range of 100 to 135°C. The heating method is not particularly limited, and may be heated from the reaction vessel wall by, for example, an outer jacket method.

In the above chlorination reaction, it is preferable to further add hydrogen peroxide to the suspension. By adding hydrogen peroxide, the rate of chlorination can be improved. It is preferable to add 0.0005 to 0.05 parts by weight of hydrogen peroxide with respect to 100 parts by weight of PVC every 1 hour of reaction time. When the addition amount is too small, the effect of improving the rate of chlorination may not be obtained. If the addition amount is too large, the thermal stability of CPVC may be lowered.

When hydrogen peroxide is added, since the chlorination rate is improved, the heating temperature can be made relatively low. For example, it may be a range of 65 to 110°C.

At the time of the chlorination, the chlorination after the point of time reaching 5% by weight from the final chlorine content is carried out in the range of 0.010 to 0.015 kg/PVC-Kg·5 min, and 3 from the final chlorine content. The chlorination after the time point at which the weight% is reached immediately before is carried out in a range of 0.005 to 0.010 kg/PVC-Kg·5 min of a chlorine consumption rate. Here, the chlorine consumption rate indicates the amount of chlorine consumption for 5 minutes per 1 kg of raw material PVC.

By carrying out chlorination by the above method, the final chlorine content is 65% by weight or more and less than 72% by weight, and the structural unit (a) -CCl ₂ -and the structural unit (b) -CHCl- and the structural unit (c) -CH _2- The proportion of the structural unit (a) is 17.5 mol% or less, the proportion of the structural unit (b) is 46.0 mol% or more, and the proportion of the structural unit (c) is 37.0 mol% or less, and There is little non-uniformity in the chlorinated state, and CPVC excellent in thermal stability can be obtained.

A molded article is obtained by adding and molding a heat stabilizer to the chlorinated vinyl chloride resin prepared as described above. As the molding method, any conventionally known production method may be employed, and examples thereof include an extrusion molding method and an injection molding method.

Another component may be mixed with the heat stabilizer.

In the manufacturing process, if necessary, additives such as stabilization aids, lubricants, processing aids, impact modifiers, heat resistance improvers, antioxidants, ultraviolet absorbers, light stabilizers, fillers, thermoplastic elastomers, and pigments may be mixed with CPVC. By mixing the stabilizing aid, the thermal stability of the molded article can be further improved.

The method of mixing the heat stabilizer and other additives with CPVC is not particularly limited, and examples thereof include a method by hot blending and a method by cold blending.

It does not specifically limit as said antioxidant, A phenol-type antioxidant, a phosphoric acid-type antioxidant, a sulfur-type antioxidant, an amine-type antioxidant, etc. can be used. These may be used individually or may use 2 or more types together.

As the hydrotalcite compound, any conventionally known hydrotalcite compound can be used. The hydrotalcite compound may be a natural product or a synthetic product. A double salt compound composed of magnesium and aluminum is preferably used.

The zeolite compound is an aluminosilicate of an alkali or alkaline earth metal having a zeolite crystal structure, such as A-type, X-type, Y-type and P-type zeolites, mordenite, analsite, sodalite group aluminosilicate, and Noptyrolite, erionite, chabasite, etc. are mentioned.

The hydrotalcite compound and/or the zeolite compound may be added alone or in combination. When the amount of addition is small, the thermal stability effect is not exhibited, and when the amount is increased, the color becomes colored.Therefore, for 100 parts by weight of CPVC, the preferable lower limit is 0 parts by weight, the more preferable lower limit is 0.05 parts by weight, and the more preferable lower limit is 0.1 parts by weight. Parts, a preferable upper limit is 2.0 parts by weight, a more preferable upper limit is 1.2 parts by weight, and a more preferable upper limit is 0.8 parts by weight.

Examples of the lubricant include internal lubricants and external lubricants. The internal lubricant is used for the purpose of preventing frictional heat generation by lowering the flow viscosity of the molten resin during molding processing. It does not specifically limit as said internal lubricant, For example, butyl stearate, lauryl alcohol, stearyl alcohol, stearic acid, bisamide, etc. are mentioned. These may be used alone or in combination of two or more.

The external lubricant is used for the purpose of enhancing the sliding effect of the molten resin and the metal surface during molding processing. It does not specifically limit as an external lubricant, For example, paraffin wax, polyolefin wax, ester wax, Montan acid wax, etc. are mentioned. These may be used alone or in combination of two or more.

It does not specifically limit as a processing aid, For example, acrylic processing aids, such as an alkyl acrylate-alkyl methacrylate copolymer having a weight average molecular weight of 100,000 to 2 million, etc. are mentioned. The acrylic processing aid is not particularly limited, and examples thereof include n-butyl acrylate-methyl methacrylate copolymer, 2-ethylhexyl acrylate-methyl methacrylate-butyl methacrylate copolymer, and the like. . These may be used alone or in combination of two or more.

It does not specifically limit as an impact modifier, For example, methyl methacrylate-butadiene-styrene copolymer (MBS), chlorinated polyethylene, acrylic rubber, etc. are mentioned.

It does not specifically limit as said heat resistance improver, For example, α-methylstyrene type, N-phenylmaleimide type resin, etc. are mentioned.

It does not specifically limit as a light stabilizer, For example, light stabilizers, such as a hindered amine system, etc. are mentioned.

It does not specifically limit as an ultraviolet absorber, For example, ultraviolet absorbers, such as a salicylic acid ester system, a benzophenone system, a benzotriazole system, and a cyanoacrylate system, etc. are mentioned.

It does not specifically limit as a filler, For example, calcium carbonate, talc, etc. are mentioned.

The pigment is not particularly limited, and examples thereof include organic pigments such as azo-based, phthalocyanine-based, srene-based, and dye lake-based; inorganic pigments such as oxide-based, sulfide-selenide-based, and ferrocyanide-based inorganic pigments. have.

Although a plasticizer may be added to the molded article for the purpose of improving the workability during molding, since the thermal stability of the molded article may be lowered, it is not very preferable to use it in a large amount. It does not specifically limit as said plasticizer, For example, dibutyl phthalate, di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate, etc. are mentioned.

Further, a thermoplastic elastomer may be added to the molded article for the purpose of improving workability. The thermoplastic elastomer is not particularly limited, and examples include acrylonitrile-butadiene copolymer (NBR), ethylene-vinyl acetate copolymer (EVA), ethylene-vinyl acetate-carbon monoxide copolymer (EVACO), and vinyl chloride- Vinyl chloride-based thermoplastic elastomers such as vinyl acetate copolymers and vinyl chloride-vinylidene chloride copolymers, styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, urethane-based thermoplastic elastomers, polyester-based thermoplastic elastomers, and polyamide-based thermoplastic elastomers. have. These thermoplastic elastomers may be used alone or in combination of two or more.

According to the method as described above, a molding resin composition having excellent thermal stability and a molded article molded from the resin composition can be manufactured.

Example

Next, embodiments of the present invention will be described using the following examples. However, the present invention is not limited to the following examples.

[Example 1]

(Preparation of chlorinated vinyl chloride resin)

200 kg of ion-exchanged water and 56 kg of vinyl chloride resin having an average polymerization degree of 1000 were put into a reaction vessel made of a glass lining having an inner volume of 300 liters. The mixture was stirred, and water was further added to the reaction vessel, and the mixture was dispersed in water. Subsequently, the pressure was reduced to remove oxygen in the reaction vessel, and the temperature was increased to 90°C.

Next, chlorine was supplied into the reaction vessel so that the partial pressure of chlorine was 0.4 MPa, and 0.2% by weight of hydrogen peroxide was added at a rate of 1 part by weight per hour (320 ppm/hour), while chlorination reaction was performed. The reaction was continued until the chlorine content of the chlorinated vinyl chloride resin became 61% by weight. When the chlorine content of the chlorinated vinyl chloride resin reaches 61% by weight (just before 5% by weight), the addition amount of 0.2% by weight hydrogen peroxide is reduced to 0.1 parts by weight per hour (200 ppm/hour), and the average chlorine consumption rate is reduced. It was adjusted to be 0.012 kg/PVC-kg·5 min to proceed with chlorination. Further, when the chlorine content reaches 63% by weight (just before 3% by weight), the addition amount of 0.2% by weight hydrogen peroxide is reduced to 150 ppm/hour per hour, and the average chlorine consumption rate is 0.008 kg/PVC-kg·5 min It adjusted so that chlorination was advanced. In this way, a chlorinated vinyl chloride resin having a chlorine content of 65.6% by weight was obtained.

(Production of heat stabilizer)

In order to use it as a heat stabilizer, a compound of formula Ca _0.9 Mg _0.1 (OH) ₂ was prepared.

1 mol/liter of Ca(OH) ₂ slurry 1 liter was put into a 2 liter volume beaker, and, stirring at 30 degreeC, 500 milliliters of 0.2 mol/liter MgCl ₂ aqueous solution were added to this. The reaction product was filtered and washed with water, and the resulting cake was dispersed in 1 liter of water. This was heated to about 80°C and, while stirring, a solution in which 1 g of sodium stearate was dissolved in 100 milliliters of warm water (about 80°C) was added to perform surface treatment. This was filtered, washed with water, and then dried. With respect to the dried product, chemical composition analysis was performed using the ICP emission spectrometry. As a result of chemical composition analysis, it was confirmed that the obtained compound was Ca _0.9 Mg _0.1 (OH) ₂ .

(Production of chlorinated vinyl chloride resin molded body)

Using the obtained chlorinated vinyl chloride resin, a heat stabilizer, and partial ester of a polyhydric alcohol, a chlorinated vinyl chloride resin composition was obtained. With respect to 100 parts by weight of the chlorinated vinyl chloride resin, 3.0 parts by weight of a heat stabilizer and 0.3 parts by weight of a polyhydric alcohol were used. Dipentaerythritol adipic acid ester was used as a partial ester of a polyhydric alcohol. In addition, 0.3 parts by weight of sodium adipic acid (manufactured by REAGENS, ``B-NT/7222'') as a stabilizing aid, 5 parts by weight of MBS (manufactured by Kaneka, ``Ganeace M-511'') as an impact modifier (Mitsui Chemicals, "Hiwax220MP") 2 parts by weight, fatty acid ester lubricant (Emerio Leo Chemicals Japan, "LOXIOL G-32") 0.3 parts by weight were used. The above components were uniformly mixed with a super mixer to obtain a chlorinated vinyl chloride resin composition. Further, as a result of measurement according to JIS K 0070 (1992), the hydroxyl value of the dipentaerythritol adipate ester was 900, and it was confirmed that a part of the hydroxyl group was not esterified.

The obtained chlorinated vinyl chloride resin composition was supplied to a twin-screw twin-directional conical extruder ("SLM-50" manufactured by Osada Corporation) having a diameter of 50 mm, and an external shape of 20 mm and a thickness of 3 mm at a resin temperature of 205°C. A pipe-shaped molded article was produced.

[Example 2]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the amount of the heat stabilizer was changed as described in Table 1.

[Example 3]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1 except that the compound of the formula Ca _0.9 Mg _0.1 O was used instead of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ as a heat stabilizer.

[Example 4]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the amount of dipentaerythritol adipic acid ester was changed as described in Table 1.

[Example 5]

Except that the ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as shown in Table 1, and 0.5 parts by weight of hydrotalcite was used instead of 0.3 parts by weight of sodium adipate as a stabilizing aid, Similarly, a chlorinated vinyl chloride resin and a molded article were produced.

[Example 6]

The ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as shown in Table 1, and the compound of the formula Ca _0.5 Mg _0.5 (OH) ₂ was replaced with the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ as a heat stabilizer. A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that 0.5 parts by weight of hydrotalcite was used instead of 0.3 parts by weight of sodium adipic acid as a stabilizing aid.

[Example 7]

The ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as shown in Table 1, and the compound of the formula Ca _0.9 Mg _0.1 O was replaced with 3.0 parts by weight of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ as a heat stabilizer. Example 1 except that 7.0 parts by weight was used, dipentaerythritol was used in place of dipentaerythritol adipic acid ester, and 0.5 parts by weight of hydrotalcite was used instead of 0.3 parts by weight of sodium adipate as a stabilizing aid. In the same manner as, a chlorinated vinyl chloride resin and a molded article were produced.

[Example 8]

Chlorinated in the same manner as in Example 1, except that the ratio of the chlorine content and molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1, and dipentaerythritol was used instead of the dipentaerythritol adipate ester. A vinyl chloride resin and a molded article were produced.

[Example 9]

The ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as shown in Table 1, and the formula Ca _0.5 Mg _0.5 (OH) was replaced with 3.0 parts by weight of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ as a heat stabilizer. _A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that 7.0 parts by weight of the compound of ₂ was used, and dipentaerythritol was used instead of the dipentaerythritol adipate ester.

[Example 10]

The ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as shown in Table 1, and a compound of the formula Ca _0.9 Mg _0.1 O was used instead of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ as a heat stabilizer. , A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that dipentaerythritol was used instead of the dipentaerythritol adipic acid ester.

[Example 11]

Chlorinated in the same manner as in Example 1, except that the ratio of the chlorine content and molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1, and dipentaerythritol was used instead of the dipentaerythritol adipate ester. A vinyl chloride resin and a molded article were produced.

[Example 12]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the amount of dipentaerythritol adipate was changed to 2.3 parts by weight.

[Example 13]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that 0.5 parts by weight of β-diketone was used together with 0.3 parts by weight of sodium adipate as a stabilizing aid.

[Example 14]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the amount of the heat stabilizer was changed as described in Table 1.

[Example 15]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the amount of the heat stabilizer was changed as described in Table 1.

[Example 16]

In the same manner as in Example 1, except that 0.2 parts by weight of dipentaerythritol adipic acid ester and 0.1 parts by weight of dipentaerythritol were used instead of 0.3 parts by weight of dipentaerythritol adipic acid ester, a chlorinated vinyl chloride resin and a molded article Produced.

[Example 17]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1 except that pentaerythritol adipic acid ester was used instead of the dipentaerythritol adipic acid ester.

Further, as a result of measurement in the same manner as in Example 1, the hydroxyl value of the pentaerythritol adipate ester was 880, and it was confirmed that some of the hydroxyl groups were not esterified.

[Example 18]

As a stabilizing aid, a chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that 0.3 parts by weight of magnesium stearate was used.

[Example 19]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that 4.0 parts by weight of magnesium stearate was used as the stabilizing aid.

[Example 20]

As a stabilization aid, a chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that 0.3 parts by weight of magnesium stearate was further used.

[Example 21]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1 except that 0.3 parts by weight of zinc stearate was used as a stabilizing aid.

[Example 22]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that 4.0 parts by weight of zinc stearate was used as the stabilizing aid.

[Comparative Example 1]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1.

[Comparative Example 2]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1.

[Comparative Example 3]

As a heat stabilizer, a chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the compound of the formula Ca _0.0 Mg _1.0 (OH) ₂ was used instead of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ .

[Comparative Example 4]

As a heat stabilizer, a chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1 except that the compound of the formula Ca _1.0 Mg _0.0 (OH) ₂ was used instead of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ .

[Comparative Example 5]

The ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as shown in Table 1, and as a heat stabilizer, instead of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ , the formula Ca _0.5 Mg _0.5 (OH) ₂ A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1 except that the compound was used and dipentaerythritol adipate was not used.

[Comparative Example 6]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the ratio of the molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1.

[Comparative Example 7]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1.

[Comparative Example 8]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1.

[Comparative Example 9]

As the heat stabilizer, in the same manner as in Example 1, except that 2,4-diamino-6-hydroxypyrimidine (DHAP) was used in place of the compound of formula Ca _0.9 Mg _0.1 (OH) ₂ , and A molded body was produced.

[Comparative Example 10]

The same as in Example 1, except that the ratio of the molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1, and DHAP was used instead of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ as a heat stabilizer. A chlorinated vinyl chloride resin and a molded article were prepared.

[Comparative Example 11]

Example 1, except that the ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1, and DHAP was used instead of the compound of the formula Ca _0.9 Mg _0.1 (OH) ₂ as a heat stabilizer. In the same manner as, a chlorinated vinyl chloride resin and a molded article were produced.

[Comparative Example 12]

Examples except that the ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as shown in Table 1, and 0.5 parts by weight of β-diketone was used together with 0.3 parts by weight of sodium adipate as a stabilizing aid. In the same manner as in 1, a chlorinated vinyl chloride resin and a molded article were produced.

[Comparative Example 13]

A chlorinated vinyl chloride resin and a molded article were produced in the same manner as in Example 1, except that the ratio of the chlorine content and the molecular structure of the chlorinated vinyl chloride resin was changed as described in Table 1.

[analysis]

The chlorine content, UV absorbance, and de-HCl time of the chlorinated vinyl chloride resin related to each of the Examples and Comparative Examples were measured. Moreover, molecular structure analysis was performed, and the mol% of -CCl ₂ -, -CHCl-, and -CH ₂ -and the mol% of the VC unit of four or more trains were measured. Each measurement method is described in detail below. Table 1 shows the measurement results.

<Measurement of chlorine content>

Measurement was carried out in accordance with JIS K 7229.

<Molecular structure analysis>

The measurement was performed according to the NMR measurement method described in R. A. Komoroski, R. G. Parker, J. P. Shocker, Macromolecules, 1985, 18, 1257-1265.

The NMR measurement conditions are as follows.

Equipment: FT-NMR (JEOL, JNM-AL-300)

Measurement core: 13 C (complete proton decoupling)

Pulse width: 90 °

PD: 2.4 sec

Solvent ： o-dichlorobenzene ： deuterated benzene (C5D5) = 3 ： 1

Sample concentration: about 20%

Temperature ： 110 ℃

Reference substance: The signal at the center of benzene was set to 128 ppm.

Number of integrations: 20000 times

<Measurement of UV absorbance (216 nm)>

UV absorbance at a wavelength of 216 nm was measured under the following measurement conditions.

Equipment: Magnetic spectrophotometer (Hitachi Manufacturing, U-3500)

Solvent ： THF

Concentration: Sample 20 mg/THF 25 ml...800 ppm (Examples 1 to 7, 12 to 19 and Comparative Examples 1, 3, 4, 6, 8 to 13)

: Sample 10 mg/THF 25 ml...400 ppm (Examples 8 to 11 and Comparative Examples 2, 5 and 7)

<De-HCl time>

1 g of the obtained chlorinated vinyl chloride resin was put in a test tube, heated at 190°C using an oil bath, and the generated HCl gas was recovered, dissolved in 100 ml of ion-exchanged water, and the pH was measured. From the pH value, how many g of HCl was generated per million g of the chlorinated vinyl chloride resin was calculated, and the time for this value to reach 7000 ppm was measured.

[evaluation]

The static thermal stability, dynamic thermal stability, and mechanical properties of the chlorinated vinyl chloride resin related to each Example and Comparative Example were measured. Moreover, the appearance state of the molded article was observed. Each measurement method is described in detail below. Table 1 shows their results. In addition, in the table, the numerical value for which a unit is not described is parts by weight.

<Static thermal stability>

The chlorinated vinyl chloride resin composition according to each Example and Comparative Example was supplied to two 8-inch rolls, and kneaded at 205°C for 3 minutes to produce a sheet having a thickness of 1.0 mm. The obtained sheet was heated in a 200 degreeC gear oven, and the coloring start time (minute) and foaming or blackening time (minute) were measured. The time to be colored yellow was defined as the time to start coloring, and the time until foaming or blackening was taken as the foaming/blackening time.

<Dynamic thermal stability>

The chlorinated vinyl chloride resin composition according to each Example and Comparative Example was supplied to a Plastmill ("Laboplast Mill" manufactured by Toyo Seiki Co., Ltd.), kneaded at a rotation speed of 50 rpm, 195°C, and a filling amount of 63 g, and the gelation time ( Seconds) was measured. The time from the start of kneading until the kneading torque peaked was taken as the gelation time. Moreover, after gelation, kneading and heating were continued again, and the decomposition time (minute) of the chlorinated vinyl chloride resin was measured. The time from the start of kneading until the stable kneading torque starts to rise again after gelation was taken as the decomposition time.

＜Machine properties (Izot impact strength, tensile strength, tensile modulus, thermal deformation temperature)＞

The chlorinated vinyl chloride resin composition according to each Example and Comparative Example was supplied to two 8-inch rolls, and kneaded at 205°C for 3 minutes to produce a sheet having a thickness of 1.0 mm. The obtained sheets were stacked, preheated for 3 minutes by a press at 205°C, and then pressed for 4 minutes to obtain a press plate having a thickness of 3 mm. From the obtained press plate, the test piece was cut by machining. Using this test piece, the tensile strength and the tensile modulus were measured according to ASTM D638. Moreover, the heat distortion temperature was measured with a load load of 186 N/cm<2> in conformity with ASTM D648. In addition, the heat distortion temperature was measured after annealing the obtained press plate in a 90 degreeC gear oven for 24 hours.

<Appearance observation of molded body>

The pipe-shaped molded article according to each Example and Comparative Example was air-cooled at room temperature for 5 minutes after molding, and then the surface condition was visually observed, and the presence or absence of bubbles, the presence or absence of stripes, and the presence or absence of soot (discoloration) were measured.

<Results>

All of the resin compositions according to Examples 1 to 22 exhibited higher thermal stability and mechanical properties than the resin composition according to the comparative example. Further, the molded articles according to Examples 1 to 12, 14 and 16 to 22 hardly observed foaming, streaks, soot, and the like, and it was found that they had an appearance superior to those of the molded articles according to the comparative examples.

In Example 12, the heat distortion temperature was relatively low. From this point of view, it was found that when the total content of the polyhydric alcohol and the partial ester of the polyhydric alcohol increased, the heat distortion temperature tends to decrease.

Example 13 contains β-diketone as a stabilizing aid. In Example 13, streaks were observed in the appearance of the molded article. From this point of view, it was shown that the molded article containing β-diketone tends to deteriorate its appearance. On the other hand, from the results of Examples 1 to 11, it was shown that according to the present invention, sufficient thermal stability and mechanical properties were obtained even without the use of β-diketone.

In Example 14, compared with Example 1, the thermal stability was slightly low. From this point of view, it was found that the thermal stability was further increased by setting the content of the thermal stabilizer to 0.4 parts by weight or more.

In Example 15, compared with Example 1, the thermal stability was high, but streaks occurred in the appearance of the molded article. It has been shown that by setting the content of the heat stabilizer to 10 parts by weight or less, it is possible to achieve both high thermal stability and good appearance of the molded article.

[Table 1-1]

[Table 1-2]

Industrial availability

Advantageous Effects of Invention According to the present invention, it is possible to provide a resin composition for molding containing a chlorinated vinyl chloride resin and a molded article thereof.

Claims (16)

A resin composition for molding containing a chlorinated vinyl chloride resin, a heat stabilizer, and a partial ester of a polyhydric alcohol and/or a polyhydric alcohol,
The chlorine content in the chlorinated vinyl chloride resin is 65% by weight or more and less than 72% by weight,
The chlorinated vinyl chloride resin is based on the total number of moles of the structural unit (a) -CCl ₂ -, the structural unit (b) -CHCl- and the structural unit (c) -CH ₂ -, of the structural unit (a). The ratio is 17.5 mol% or less, the ratio of the structural unit (b) is 46.0 mol% or more, the ratio of the structural unit (c) is 37.0 mol% or less,
The heat stabilizer is a compound represented by the general formula Ca _1-x Mg _x (OH) ₂ (in the formula, x satisfies the relationship represented by the inequality 0 <x <1) and the general formula Ca _1-y Mg _y Contains at least one of the compounds represented by O (in the formula, y satisfies the relationship represented by inequality 0<y<1),
The total content of polyhydric alcohol and/or partial ester of polyhydric alcohol in the resin composition for molding is in the range of 0.05 to 3 parts by weight when the content of the chlorinated vinyl chloride-based resin is 100 parts by weight,
The resin composition for molding, wherein the total content of the polyhydric alcohol and/or the partial ester of the polyhydric alcohol in the molding resin composition is in the range of 1 to 10 parts by weight when the content of the heat stabilizer is 100 parts by weight. The method of claim 1,
The resin composition for molding, wherein the chlorine content in the chlorinated vinyl chloride resin is 65% by weight or more and less than 69% by weight. The method of claim 1,
The resin composition for molding, wherein the chlorine content in the chlorinated vinyl chloride resin is 69% by weight or more and less than 72% by weight. The method of claim 1, 2 or 3,
The chlorinated vinyl chloride resin is the ratio of the structural unit (b) to the total number of moles of the structural unit (a) -CCl ₂ -, the structural unit (b) -CHCl- and the structural unit (c) -CH _2- It is 58.0 mol% or more, and the ratio of the structural unit (c) is 35.8 mol% or less, The resin composition for molding characterized by the above-mentioned. The method according to claim 1 or 2,
The resin composition for molding, wherein the chlorinated vinyl chloride-based resin has a UV absorbance at a wavelength of 216 nm of 0.8 or less. The method of claim 1 or 3,
The resin composition for molding, wherein the chlorinated vinyl chloride-based resin has a UV absorbance at a wavelength of 216 nm of 8.0 or less. The method according to claim 1 or 2,
The resin composition for molding, characterized in that the time required to reach 7000 ppm of the amount of HCl dehydrogenated at 190°C from the chlorinated vinyl chloride resin is 60 seconds or more. The method of claim 1 or 3,
The resin composition for molding, characterized in that the time required to reach 7000 ppm of the amount of HCl dehydrogenated at 190°C from the chlorinated vinyl chloride resin is 100 seconds or more. The method of claim 1, 2 or 3,
A resin composition for molding characterized in that it does not contain β-diketone. The method of claim 1, 2 or 3,
The content of the heat stabilizer in the molding resin composition is in the range of 0.4 to 10 parts by weight when the content of the chlorinated vinyl chloride resin is 100 parts by weight. The method of claim 1, 2 or 3,
Further, a resin composition for molding, characterized in that it contains a stabilizing aid. The method of claim 11,
The resin composition for molding, characterized in that the stabilizing aid contains at least one selected from sodium adipate and hydrotalcite. The method of claim 11,
The resin composition for molding, characterized in that the stabilizing aid contains an organic acid salt. The method of claim 11,
The resin composition for molding, characterized in that the stabilizing aid contains a higher fatty acid salt. A molded article molded from the resin composition for molding according to claim 1, 2 or 3. delete